“It’s like concrete if you fall off while you’re going fast. It’s completely unjustified to expose detainees to this kind of experience, regardless of what sort of information they may have,” he said.

Bauer said possible side effects included “getting water up your nose, getting a really red back when you fall off, and really stiff shoulders the next day.”

The revelations came as National Intelligence Director Mike McConnell presented his annual threat assessment to Congress. The agency did not rule out using related techniques such as snowboarding or skateboarding in the future.